QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

HOME  |   SEARCH  |   ARCHIVE  |   SUBSCRIBE  |   CONTACT  |   HELP

This Article Full Text (PDF) Submit an eLetter Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Klockgether, T. Articles by Sontag, K. H. Search for Related Content PubMed PubMed Citation Articles by Klockgether, T. Articles by Sontag, K. H.

 Previous Article  |  Next Article 

Journal of Neuroscience, Vol 6, 1702-1711, Copyright © 1986 by Society for Neuroscience

ARTICLE

The rat ventromedial thalamic nucleus and motor control: role of N- methyl-D-aspartate-mediated excitation, GABAergic inhibition, and muscarinic transmission

T Klockgether, M Schwarz, L Turski and KH Sontag

The rat ventromedial thalamic nucleus (VM) is a point of convergence of several pathways that are supposed to be involved in motor control. Cortical fibers terminating within this nucleus use an excitatory amino acid, possibly L-glutamate, as their transmitter. Excitatory amino acids are known to interact with N-methyl-D-aspartate (NMDA), kainate, and quisqualate receptors, the presence of which has been demonstrated within the thalamus, gamma-Amino-butyrate (GABA) has been identified as the transmitter of the basal ganglia afferents to the VM, whereas cerebellar afferents to the VM are supposed to release ACh acting on muscarinic receptors. The present study investigates the behavioral and motor consequences of local injections of drugs into the VM, which specifically interact with NMDA, GABA, and muscarine receptors. Both the NMDA antagonist (-)2-amino-7-phosphonoheptanoate [(-)AP7], and the GABA agonist muscimol, but not the muscarinic antagonist scopolamine, induced catalepsy and limb rigidity. Both the (-)AP7- and muscimol- induced catalepsy were antagonized by coadministration of NMDA and the GABA antagonist bicuculline. The (-)AP7-induced catalepsy was characterized as an akinetic-rigid syndrome, in which the ability to induce a phasic activation of a set of muscles is lost and replaced by exaggerated tonic muscular responses. NMDA, bicuculline, and the muscarinic agonist bethanechol induced an increase in locomotor activity. The present study provides evidence that an imbalance between NMDA-mediated excitation and GABAergic inhibition within the rat VM leads to disturbances of motility, whereas muscarinic transmission within this nucleus appears to be of minor importance.

This article has been cited by other articles:

				M. Marti, C. Trapella, R. Viaro, and M. Morari The Nociceptin/Orphanin FQ Receptor Antagonist J-113397 and L-DOPA Additively Attenuate Experimental Parkinsonism through Overinhibition of the Nigrothalamic Pathway J. Neurosci., February 7, 2007; 27(6): 1297 - 1307. [Abstract] [Full Text] [PDF]

Home  |   Search  |   Archive  |   Subscribe  |   Contact  |   Help